[PATCH v5] enhance NUMA affinity heuristic

[Kaisen You]

Trying to allocate memory on the first detected numa node has less
chance to find some memory actually available rather than on the main
lcore numa node (especially when the DPDK application is started only
on one numa node).

Fixes: 705356f0811f ("eal: simplify control thread creation")
Fixes: bb0bd346d5c1 ("eal: suggest using --lcores option")
Cc: sta...@dpdk.org

Signed-off-by: David Marchand <david.march...@redhat.com>
Signed-off-by: Kaisen You <kaisenx....@intel.com>
---
Changes since v4:
- mod the patch title,

Changes since v3:
- add the assignment of socket_id in thread initialization,

Changes since v2:
- add uncommitted local change and fix compilation,

Changes since v1:
- accomodate for configurations with main lcore running on multiples
  physical cores belonging to different numa,
---
 lib/eal/common/eal_common_thread.c | 1 +
 lib/eal/common/malloc_heap.c       | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/lib/eal/common/eal_common_thread.c 
b/lib/eal/common/eal_common_thread.c
index 38d83a6885..21bff971f8 100644
--- a/lib/eal/common/eal_common_thread.c
+++ b/lib/eal/common/eal_common_thread.c
@@ -251,6 +251,7 @@ static void *ctrl_thread_init(void *arg)
        void *routine_arg = params->arg;
 
        __rte_thread_init(rte_lcore_id(), cpuset);
+       RTE_PER_LCORE(_socket_id) = SOCKET_ID_ANY;
        params->ret = rte_thread_set_affinity_by_id(rte_thread_self(), cpuset);
        if (params->ret != 0) {
                __atomic_store_n(&params->ctrl_thread_status,
diff --git a/lib/eal/common/malloc_heap.c b/lib/eal/common/malloc_heap.c
index d7c410b786..3ee19aee15 100644
--- a/lib/eal/common/malloc_heap.c
+++ b/lib/eal/common/malloc_heap.c
@@ -717,6 +717,10 @@ malloc_get_numa_socket(void)
                        return socket_id;
        }
 
+       socket_id = rte_lcore_to_socket_id(rte_get_main_lcore());
+       if (socket_id != (unsigned int)SOCKET_ID_ANY)
+               return socket_id;
+
        return rte_socket_id_by_idx(0);
 }
 
-- 
2.34.1